1. Field of the Invention
The present invention relates to a tube and, more particularly, to a tube of a radiator for cooling the engine of a car.
2. Description of the Related Art
A conventional radiator of the engine of a car in accordance with the prior art shown in FIGS. 1 and 2 comprises a radiator core. The radiator core includes a plurality of tubes 10, and a plurality of cooling fins 12 connected with the tubes 10. Each of the tubes 10 has a first side formed with a first curved face “A” and a second side formed with a second curved face “B” which is located opposite to the first curved face “A”. Each of the tubes 10 is formed by a sheet plate which is made of aluminum material. The sheet plate of each of the tubes 10 has two opposite ends connected with each other to form a connecting portion 11. The connecting portion 11 of the sheet plate is located at the first curved face “A” of each of the tubes 10. The second curved face “B” of each of the tubes 10 has a thickness smaller than that of the first curved face “A” so that the second curved face “B” of each of the tubes 10 has a weaker strength. Thus, when the tubes 10 are subjected to the thermal expansion and contraction, the stress and the shock during the cooling process, the second curved face “B” of each of the tubes 10 easily produces breaches “B1” during a long-term utilization, thereby decreasing the lifetime of each of the tubes 10, and thereby easily producing leakage.